Since the Sunday night when President Obama told the world of Osama bin Laden's demise curiosity about the Navy SEALs who killed and has been insatiable. Now one former high level officer. This pulling back a bit more of the -- describing what these men go through. To be called -- sealed here's ABC's John Donvan. This used to be something that none of an instrument to see. Much less videotape and put on television. The Navy SEALs didn't only operate in the shadows they trained -- them to their whole story stayed shrouded in mystery. They're secret missions stayed secret for the rest of us. But when they got Osama bin Laden. And when their snatching back in American cargo ship captain who was taken by pirates and rescuing two aid workers held hostage in Somalia. Then suddenly it's like the seals are headline makers add to that but some of them are writing books about -- adventures that's. And -- acting in a movie about the real experience. By the way live bullets that's what -- pay back. Just can no longer quite call -- the military unit that no one ever talked about. Take -- in Denver he played lieutenant commander -- an act of -- a film that used dozens of seals and went on to -- eighty million dollars at the box office and he did some pretty decent acting sir we have a foreign nationals and into our country needless to say they are no big fan of -- And now with the help of a professional writer he's doing some pretty decent story telling in a new book called damn few. I just think -- at this moment our history when the heat is on the dimensions are getting. Press and and coverage -- as a single. But time will tell I think we are in the public eye and I think that mythology is something that people are hugely hugely interest -- and they have an appetite for I had an opportunity I field. To authentically represent that hope we do it from an honorable. Point of view it's mostly his own story he tells in -- few -- he joined the seals after college. And they didn't want -- at first they didn't I I put in my first application and they said no I'm -- -- -- that weigh in on I think community really values. Resiliency and toughness and focus and at a never quit attitude so for me. When they said no -- -- that I'm gonna cut it. Denver did not quit he re applied and went on to survive the seals brutal hell week in training join the teams and deployed all over the world. Including the deadly -- on bar province in Iraq I was in for your family living the other side of this. The families I feel are the ones that pay the price of our choices they really are every bit a part of our experience and frankly they're the ones that are back home. You know hoping and praying and believing that you're gonna come home. And really even his family didn't quite know what he did it work every day. But the movie was revealing in that way. It was incredibly eye opening to actually see. February and cut it may see an alert running around in the -- for me it -- like apple subject of what you're getting when your I appreciated it actually. And no system to appreciate the -- you. Washington which should be a good thing for the unit but there's a catch. Politicians are saying we should have more of that -- think more seals not necessarily Smart says Rourke. It scares me and to be honest we don't know if there's going to be a dilution of the town or our focus on mission sets and how that's gonna impact the team I just think as a culture we wanna be deliberate about how we move that -- He's noticed for example but in some training exercises. Guys who fail are getting more and more do overs to try again like ten or 12 times I am concerned about twelve attempts to get through a program weren't used to just before but I also was cognizant of the fact we're going through training that one of the things that -- -- does not -- those instructors get away from. That focus -- -- on on making it harder to make it matter usually there are about 2500 seals and service many more than that apply and start to training. But most don't make it so what does it take I think it's a tremendous desire to to succeed. I think it's absolute inability to have to quit. No matter how tough things -- that's why they call themselves the damn few. A term more of -- snow because the seals are coming just that much more out of the shadows. For Nightline I'm John Donvan in New York. -- -- is in bookstores now and it's published by hyperion which shares of parent company. Disney with ABC news thanks to John.

This transcript has been automatically generated and may not be 100% accurate.

{"id":18543078,"title":"Former SEAL on Coming Out of the Shadows","duration":"4:27","description":"Author, 'Act of Valor' star Rorke Denver talks about the spotlights on the military's secret unit.","url":"/Nightline/video/seal-coming-shadows-18543078","section":"Nightline","mediaType":"Default"}